1. Field of the Invention
This invention is related to a safety enclosure for a Huber needle in order to keep the Huber needle from inadvertently sticking a medical practitioner during installing and removal of the Huber needle in conjunction with an animal body which includes humans.
2. Description of the Related Art
Within the medical field, more and more patients require the use of vascular access devices as part of their care. Vascular access devices (implanted ports) are used on human patients to supply pain drugs, chemotherapy, antibiotics, anti-viral or anti-fungal drugs as well as for hydration and nutrition. In recent years, there has been a substantial increase in the number of patients with implanted ports. An implanted port requires a special needle to be inserted through the skin of the patient and into the port. The most common type of such a needle includes a ninety degree bend. This type of needle is called a Huber needle. Because of the configuration of the needle, removing of the Huber needle at the end of the infusion therapy is particularly dangerous exposing the medical practitioner to a high degree of risk of inadvertent needlestick injury.
Huber needles are usually designed for longer term infusion therapy. The angular relationship of the needle allows the Huber needle to be more safely anchored to the skin around the port. These needles are commonly left in place for a period of several days, weeks and possibly even months. It is common for the Huber needles to have attached thereto a wing assembly with the wing assembly to be used for securing the Huber needle to the patient by taping the wing members of the wing assembly to the skin of the patient thus facilitating insertion and removal of the Huber needle.
The procedure of removing a Huber needle from an implanted port commonly produces what is called “bounceback” which comprises a rebounding effect. When the needle is mounted in conjunction with the port, the rubber of the port tightly binds about the needle. A substantial force is required when pulling on the needle in order to get it to release from the port. The medical practitioner thus has to pull hard in order to get the needle to release from the port. Once the needle is released, the muscular movement of the medical practitioner then relaxes and an opposite movement takes place, which is called bounceback. Frequently, this bounceback drives the Huber needle point down and can be driven into the medical practitioner's hand or arm. This is called a needlestick injury. The needle is contaminated with the blood of the patient. The patient could have a serious transferable disease, such as AIDS. The medical practitioner could catch the same disease.
There have been prior art types of devices that have been sold for the purpose of decreasing or eliminating needlestick injury. One device consists of a protective member that fits over the port. The medical practitioner then uses a hemostat to pull the needle up in the device for containment during removal of the needle from the patient. The device and the needle is then disposed of. One disadvantage of this technique is that it requires a significant change in the procedure having to do with the removal of the Huber needle and it also requires the use of additional equipment, the hemostat, and it requires a significant amount of dexterity. A second type of device is a scissors type of device formed of two blades which are slid under wings of the needle and against the patient's skin. When the needle is being removed, the bottom blade of the device stabilizes the device while the upper blade pulls out the needle. The needle is held in the blade, but the sharp end remains exposed. This device also requires a significant change in technique in the removing of Huber needles and has a further disadvantage in that it does not fully contain the sharp end of the needle. There is also a device called a Huberlock (trademark). The Huberlock requires a change in technique but it does eliminate pulling a bare needle out of a port. Also, the Huberlock has the disadvantage that it does not fully contain the sharp end of the needle. Also, the Huberlock requires the use of additional equipment which comprises a plastic holder to be used in conjunction with the needle.
Probably the best needle protection device is disclosed within U.S. Pat. No. 5,951,522, entitled Hypodermic Needle Safety Enclosure. This device is not automatically retracting but retracts solely by the application of a manual force. It would be desirable to construct a hypodermic safety needle enclosure which would automatically retract the needle when the needle is pulled from the port eliminating the possibility of bounceback and therefore completely eliminating the possibility of any needlestick injury.